OBJECTIVES: 1. Studies will be made on the blood circulation in the eye and the optic nerve under conditions of elevated intraocular pressure. 2. Studies will be made on the control of intraocular blood circulation exerted by the parasympathetic nerves. 3. Studies will be made on the control of aqueous humor production and on drug effects on aqueous formation. 4. Studies on the supply of nutrients to the different intraocular tissues will be continued.